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What is IPv6?
	Successor of currently used IP Version 4
	Specified 1995 in RFC?  2460
Why?
	Address space in IPv4 too small

Advantages?
	stateless autoconfiguration
	multicast obligatorisch
	IPsec obligatorisch
	Mobile IP
	QoS ?
	
	Address Renumbering?
	Multihoming?
	AddressScopes?
	smaller routing tables through G

	simplified l3 header
		64bit aligned
		no checksum (l4 or l2)
		no fragmentation at router

Disadvantages
	Not widely deployed yet
	In most cases access only possible using manual tunnel
	OS support not ideal in most cases
		W2k?
		Linux has support, but no IPsec in official tree -> USAGI
		*BSD: full support (KAME
	Application support not ideal in most cases
		not supported: 
		supported: bind8/9, apache

Deployment
	Experimental 6bone (3ffe::) has been active since 199x.
	Uses slightly different Addressing Architecture (RFC2471)
	
Why isn't it widely used yet?
	No immediate need in Europe / North America
	Big deployment cost at ISP's (Training, Routers, ..)

Technical: Address Space
	IP Version 6 Addressing Architecture (RFC2373)
		Format prefix, variable length
			001: RFC2374 addresses, 1/8 of address space
			0000 001: Reserved for NSAP (1/128)
			0000 010: Reserved for IPX (1/128)
			1111 1110 10: link-local unicast addresses (1/1024)
			1111 1110 11: site-local unicast addresses (1/1024)
			1111 1111: multicast addresses
				1111 1111 flgs scop
					flgs (0: well-known, 1:transient)
					scop (0: reserved, 1: node-local, 2: link-local, 5: site-local, 8: organization-local, e: global scope, f: reserved)
	Aggregatable Global Unicast Address Format (RFC2374)
		3bit FP (format prefix = 001)
		13bit TLA ID - Top-Level Aggregation ID
		13bit Sub-TLA - Sub-TLA Aggergation ID
		19bit NLA - Next-Level Aggregation ID
		16bit SLA - Site-Level Aggregation ID
		64bit Interface ID - derived from 48bit ethernet MAC

		2001:0000::/29 - 2001:01f8::/29 IANA
		2001:0200::/29 - 2001:03f8::/29 APNIC
		2001:0400::/29 - 2001:05f8::/29 ARIN
		2001:0600::/29 - 2001:07f8::/29 RIPE
	loopback
		::1
	unspecified:
		::0
	embedded ipv4
		IPv4-compatible address: 0::xxxx:xxxx
		IPv4-mapped IPv4 (IPv4 only node): 0::ffff:xxxx:xxxx
	anycast
		allocated from unicast addresses
		only subnet-router anycast address predefined (prefix::0000)


Technical: Header

	4bit Version: 6
	8bit Traffic Class
	20bit Flow Label
	16bit Payload Length (incl. extension hdrs)
	8bit next header (same values like IPv4, RF1700 et seq.)
	8bit hop limit (TTL)
	128bit source address
	128bit dest address
	
	extension headers:
		hop-by-hop options
		routing
		fragment
		destination options
		authentication
		encapsulating security payload

Technical: Layer 2 <-> Address mapping
	Ethernet: No more ARP, everything within ICMPv6
	No Broadcast, everything built using multicast.

	all-nodes multicast address ff02::1
	all-routers multicast address ff02::2
	
	
Technical: Address Configuration
	router discovery
		routers periodically send router advertisements
		hosts can send router solicitation to explicitly request RADV
	prefix discovery
		router includes prefix(es) in ICMPv6 router advertisements
		other nodes receive prefix advertisements and derive their final address from prefix + EUI64 of MAC address


personal git repositories of Harald Welte. Your mileage may vary